Consequently, the presence and persistence of P. aeruginosa has been identified as a marker of bronchiectasis severity, although it remains unclear whether this is causal or associated with accelerated lung function decline . IACS-10759 clinical trial frequent exacerbations experienced by bronchiectasis patients may contribute to the progressive decline of lung function , though both the aetiology and pathophysiology of exacerbations remains poorly understood. Exacerbations are frequently managed with antibiotics, however, viral infections may also be
significant in many cases but their role requires clarification . The aim of this study was to investigate the airway microbiota in NCFBr and characterise its diversity and structure. We aimed to test the hypotheses that bacterial community differences reflect the exacerbation history of the patient, that the presence or absence of culturable pathogens sculpted the structure of the airway microbiome and that the bacterial community MK 8931 would show significant change in response to the interventions used to manage patient outcomes. Results Patient cohort Patient baseline data are summarised in Table 1. The study population consisted of 25 males and 45 females.
The self-reported exacerbation rates in the preceding 12 months were available for Captisol research buy 61 of the 70 patients. Thirty-eight patients were identified as frequent exacerbators with more than 3 exacerbations in a 12 month period. At the time of sample collection 20 patients reported symptoms consistent with exacerbation (Additional file 1: Table S1). Table 1 Patient data for the cohort Demographic data All patients (n = 70) Non-exacerbated (n = 50) Exacerbated (n = 20) Age (yr) 61.6 ± 13 61.2 ± 13.4 62.5 ± 13 Female (%) 64.3 60 75 FEV (L) 1.46 1.45 1.54 Males 1.78a 1.80a 1.77a Females 1.26b 1.20b 1.45b FEV1% predicted 57.9 55.2 64.9 Frequent exacerbation (%)* (n = 61) 61.7 56 45 Culture negative (%) 38.6 22 40 H. influenzae colonisation (%) 21.4 12 45 P. aeruginosa colonisation (%) 32.8 40 15 Recent Antibiotics Interleukin-3 receptor (%)+ 24.3 22 30 *Frequency of exacerbation data (available for 61 patients). Frequent exacerbators defined as >3 episodes per annum. + Indicates treatment within the last month with antibiotics
other than maintenance colomycin or azithromycin. Values followed by different letters are significantly different (p < 0.05). When corrected for sex and height the FEV1% predicted were similar between the 2 genders. Microbial culture Sputa from 51 patients (73%) were culture positive for pathogenic microorganisms, the remainder either yielded no bacteria or non-pathogenic mixed oral flora as determined by the standard culture protocol used in the clinic (Additional file 1: Table S1). The most common organisms were P. aeruginosa found in 33% and H. influenzae in 21% of patients respectively. There were no instances of both P. aeruginosa and H. influenzae being found within a single sputum sample. Patient records showed that 24 individuals had P.